Mirror image twins

BabyCarryingVessel

Can someone explain this to me? My understanding is that 40 percent of identical twins are mirror image. What exactly is the definition of mirror image? J and K have their hair swirls on opposite sides of their crowns, plus J sucks her left thumb and K sucks her right. Are these possible signs of mirror image? Any input would be appreciated!

Annabelle7

Yes, sounds like your twins are mirror image!

 

Definition from www.proactivegenetics.com

"What are mirror image twins?

Mirror image twins are identical twins that result when a fertilized egg splits later in the embryonic stage than usual, typically from day 9 to 12. Mirror image twins tend to exhibit characteristics with reversed asymmetry (e.g., one twin is left-handed and the other is right-handed, or opposite-sided occipital hair whorls and hair partings). If this split happens much later than this, then the twins can be co-joined. A DNA-based zygosity test cannot determine if twins are mirror image twins."

 

BabyCarryingVessel

Thanks for your response! I just did a little research and I don't think they are mirror image... They are di di identicals, so that would mean they would have split early. It looks like mirror image twins split late. Plus, both of their crown swirls spin clockwise, and I just read that one would spin counterclockwise if they were mirror image. Holy cow! I found all of this very interesting!

kiwi443

I think my girls may be mirror image. It'll be interesting to see if one is right-handed and the other left-handed. Their hair whorls are on opposite sides and they each have a birthmark on opposite sides of their chests. Normally I have no trouble telling them apart, but if I look at one in a mirror I have to do a double take.

Since there isn't a test for it, it's something you figure out based on evidence. I'm finding all this multiples stuff so fascinating.

pea-kay

I don't think cowlicks or birthmarks are genetic, since my boys have both all over the place. I don't think any of mine are, since they all appear to be right-handed.